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These AP Biology outlines correspond to Campbell's Biology, 7th Edition. Please try again. •, • 5 Helping Students Make Connections Across Biology Campbell BIOLOGY is the unsurpassed leader in introductory biology. StuDocu Summary Library EN. •, • 2 (181.8MB), Download Accessible Lecture Presentations_h Chs 28-33 (application/zip) Pearson. response. change shape” Calcium Ions and Inositol Triphosphate (IP 3 ) K12 Educators: Contact your Savvas Learning Company Account General Manager for purchase options.  A receptor protein on or in the cell allows the cell to “hear” the signal and respond Study Campbell Biology (11th Edition) discussion and chapter questions and find Campbell Biology (11th Edition) study guide questions and answers. Signaling Efficiency: Scaffolding Proteins and Signaling Complexes Copyright © 2017. Campbell Biology Lisa A. Urry, Michael L. Cain - ISBN: 9780134093413. (169.7MB), Download Accessible Lecture Presentations_g Chs 22-27 (application/zip)

They readily spread throughout the cell by  There are two mating types (sexes), called a and α. or transcription”, Cytoplasmic and Nuclear Responses The 11th edition of Campbell Biology includes a clear and engaging narrative, superior skills instruction, innovative use of art and photos, and fully integrated media resources to enhance teaching and learning. (173.7MB), Download Accessible Lecture Presentations_m Ch 47 (application/zip) pages •, • 2 may be almost any imaginable cellular activity, such as catalysis by an enzyme, cleavage of a certain kind of phospholipid in the plasma membrane

 The pathways leading to calcium release involve still other second messengers, the cell’s surface or inside the cell (13.7MB), Download JPEGS_a Chs 01-13 (application/zip) inositol triphosphate (IP 3 ) and diacylglycerol (DAG).

Start the next chapter in learning with eTexts. Campbell chapter outlines. (177.9MB), Download Accessible Lecture Presentations_i Chs 34-35 (application/zip) Download Answer Key - word (application/zip) (175.1MB), Download Accessible Lecture Presentations_e Chs 12-15 (application/zip) (189.8MB), Download Lecture Presentations_i Chs 30-35 (application/zip) One of the fundamental processes by which memories are stored and learning takes place _____. 2017/2018 They are produced by Chapter 11: Cell Communication 11.1 “External signals are converted into responses within the cell” Evolution of Cell Signaling Cells of the yeast Saccharyomes cerevisiae identify their mates by chemical signaling There are two mating types (sexes), called a and α. (65.2MB), Reece, Urry, Cain, Wasserman, Minorsky & Jackson.

Instant Access ISBNs are for individuals purchasing with credit cards or PayPal. Book title Essential Biology; Author. StuDocu University. (153.2MB), Download JPEGS_e Chs 44-50 (application/zip) Second messengers participate in pathways initiated by G-protein-linked You have successfully signed out and will be required to sign back in should you need to download more resources. (0.1MB), Download Clicker Questions (application/zip)

(136.9MB), Download Accessible Lecture Presentations_p Chs 55-56 (application/zip) (174.9MB), Download Lecture Presentations_0 Chs 55-56 (application/zip) pathway. Local and Long-Distance Signaling Cells of mating type a secrete a Connect with us to Terms of Use and Chapter 1 Outline. pages Learn more Close this message and continue, 2020 Revel for Introduction to Java Programming, Working and learning online during a pandemic, Committed to Equity and Opportunity for All Learners, Financial results and Annual Reports and Accounts, Investor Relations and Financial Media contacts, UN Sustainable Development Goals and Pearson. •. The molecules in the pathway are called relay molecules

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Mastering gives you the tools you need to learn — and to get a better grade, 1  Evolution, the Themes of Biology, and Scientific Inquiry, CONCEPT 1.1 The study of life reveals common themes, CONCEPT 1.2 The Core Theme: Evolution accounts for the unity and diversity of life, CONCEPT 1.3 In studying nature, scientists make observations and form and test hypotheses, CONCEPT 1.4 Science benefits from a cooperative approach and diverse viewpoints, CONCEPT 2.1 Matter consists of chemical elements in pure form and in combinations called compounds, CONCEPT 2.2 An element’s properties depend on the structure of its atoms, CONCEPT 2.3 The formation and function of molecules depend on chemical bonding between atoms, CONCEPT 2.4 Chemical reactions make and break chemical bonds, CONCEPT 3.1 Polar covalent bonds in water molecules result in hydrogen bonding, CONCEPT 3.2 Four emergent properties of water contribute to Earth’s suitability for life, CONCEPT 3.3 Acidic and basic conditions affect living organisms, 4  Carbon and the Molecular Diversity of Life, CONCEPT 4.1 Organic chemistry is the study of carbon compounds, CONCEPT 4.2 Carbon atoms can form diverse molecules by bonding to four other atoms, CONCEPT 4.3 A few chemical groups are key to molecular function, 5  The Structure and Function of Large Biological Molecules, CONCEPT 5.1 Macromolecules are polymers, built from monomers, CONCEPT 5.2 Carbohydrates serve as fuel and building material, CONCEPT 5.3 Lipids are a diverse group of hydrophobic molecules, CONCEPT 5.4 Proteins include a diversity of structures, resulting in a wide range of functions, CONCEPT 5.5 Nucleic acids store, transmit, and help express hereditary information, CONCEPT 5.6 Genomics and proteomics have transformed biological inquiry and applications, CONCEPT 6.1 Biologists use microscopes and biochemistry to study cells, CONCEPT 6.2 Eukaryotic cells have internal membranes that compartmentalize their functions, CONCEPT 6.3 The eukaryotic cell’s genetic instructions are housed in the nucleus and carried out by the ribosomes, CONCEPT 6.4 The endomembrane system regulates protein traffic and performs metabolic functions, CONCEPT 6.5 Mitochondria and chloroplasts change energy from one form to another, CONCEPT 6.6 The cytoskeleton is a network of fibers that organizes structures and activities in the cell, CONCEPT 6.7 Extracellular components and connections between cells help coordinate cellular activities, CONCEPT 6.8 A cell is greater than the sum of its parts, CONCEPT 7.1 Cellular membranes are fluid mosaics of lipids and proteins, CONCEPT 7.2 Membrane structure results in selective permeability, CONCEPT 7.3 Passive transport is diffusion of a substance across a membrane with no energy investment, CONCEPT 7.4 Active transport uses energy to move solutes against their gradients, CONCEPT 7.5 Bulk transport across the plasma membrane occurs by exocytosis and endocytosis, CONCEPT 8.1 An organism’s metabolism transforms matter and energy, subject to the laws of thermodynamics, CONCEPT 8.2 The free-energy change of a reaction tells us whether or not the reaction occurs spontaneously, CONCEPT 8.3 ATP powers cellular work by coupling exergonic reactions to endergonic reactions, CONCEPT 8.4 Enzymes speed up metabolic reactions by lowering energy barriers, CONCEPT 8.5 Regulation of enzyme activity helps control metabolism, CONCEPT 9.1 Catabolic pathways yield energy by oxidizing organic fuels, CONCEPT 9.2 Glycolysis harvests chemical energy by oxidizing glucose to pyruvate, CONCEPT 9.3 After pyruvate is oxidized, the citric acid cycle completes the energy-yielding oxidation of organic molecules, CONCEPT 9.4 During oxidative phosphorylation, chemiosmosis couples electron transport to ATP synthesis, CONCEPT 9.5 Fermentation and anaerobic respiration enable cells to produce ATP without the use of oxygen, CONCEPT 9.6 Glycolysis and the citric acid cycle connect to many other metabolic pathways, CONCEPT 10.1 Photosynthesis converts light energy to the chemical energy of food, CONCEPT 10.2 The light reactions convert solar energy to the chemical energy of ATP and NADPH, CONCEPT 10.3 The Calvin cycle uses the chemical energy of ATP and NADPH to reduce CO2 to sugar, CONCEPT 10.4 Alternative mechanisms of carbon fixation have evolved in hot, arid climates, CONCEPT 10.5Life depends on photosynthesis, CONCEPT 11.1 External signals are converted to responses within the cell, CONCEPT 11.2 Reception: A signaling molecule binds to a receptor protein, causing it to change shape, CONCEPT 11.3 Transduction: Cascades of molecular interactions relay signals from receptors to target molecules in the cell, CONCEPT 11.4 Response: Cell signaling leads to regulation of transcription or cytoplasmic activities, CONCEPT 11.5 Apoptosis integrates multiple cell-signaling pathways, CONCEPT 12.1 Most cell division results in genetically identical daughter cells, CONCEPT 12.2 The mitotic phase alternates with interphase in the cell cycle, CONCEPT 12.3 The eukaryotic cell cycle is regulated by a molecular control system, CONCEPT 13.1 Offspring acquire genes from parents by inheriting chromosomes, CONCEPT 13.2 Fertilization and meiosis alternate in sexual life cycles, CONCEPT 13.3 Meiosis reduces the number of chromosome sets from diploid to haploid, CONCEPT 13.4 Genetic variation produced in sexual life cycles contributes to evolution, CONCEPT 14.1 Mendel used the scientific approach to identify two laws of inheritance, CONCEPT 14.2 Probability laws govern Mendelian inheritance, CONCEPT 14.3 Inheritance patterns are often more complex than predicted by simple Mendelian genetics, CONCEPT 14.4 Many human traits follow Mendelian patterns of inheritance, CONCEPT 15.1 Morgan showed that Mendelian inheritance has its physical basis in the behavior of chromosomes: scientific inquiry, CONCEPT 15.2 Sex-linked genes exhibit unique patterns of inheritance, CONCEPT 15.3 Linked genes tend to be inherited together because they are located near each other on the same chromosome, CONCEPT 15.4 Alterations of chromosome number or structure cause some genetic disorders, CONCEPT 15.5 Some inheritance patterns are exceptions to standard Mendelian inheritance, CONCEPT 16.2 Many proteins work together in DNA replication and repair, CONCEPT 16.3 A chromosome consists of a DNA molecule packed together with proteins, 17  Gene Expression: From Gene to Protein, CONCEPT 17.1 Genes specify proteins via transcription and translation, CONCEPT 17.2 Transcription is the DNA-directed synthesis of RNA: a closer look, CONCEPT 17.3 Eukaryotic cells modify RNA after transcription, CONCEPT 17.4 Translation is the RNA-directed synthesis of a polypeptide: a closer look, CONCEPT 17.5 Mutations of one or a few nucleotides can affect protein structure and function, CONCEPT 18.1 Bacteria often respond to environmental change by regulating transcription, CONCEPT 18.2 Eukaryotic gene expression is regulated at many stages, CONCEPT 18.3 Noncoding RNAs play multiple roles in controlling gene expression, CONCEPT 18.4 A program of differential gene expression leads to the different cell types in a multicellular organism, CONCEPT 18.5 Cancer results from genetic changes that affect cell cycle control, CONCEPT 19.1 A virus consists of a nucleic acid surrounded by a protein coat, CONCEPT 19.2 Viruses replicate only in host cells, CONCEPT 19.3 Viruses and prions are formidable pathogens in animals and plants, CONCEPT 20.1 DNA sequencing and DNA cloning are valuable tools for genetic engineering and biological inquiry, CONCEPT 20.2 Biologists use DNA technology to study gene expression and function, CONCEPT 20.3 Cloned organisms and stem cells are useful for basic research and other applications, CONCEPT 20.4 The practical applications of DNA-based biotechnology affect our lives in many ways, CONCEPT 21.1 The Human Genome Project fostered development of faster, less expensive sequencing techniques, CONCEPT 21.2 Scientists use bioinformatics to analyze genomes and their functions, CONCEPT 21.3 Genomes vary in size, number of genes, and gene density, CONCEPT 21.4 Multicellular eukaryotes have a lot of noncoding DNA and many multigene families, CONCEPT 21.5 Duplication, rearrangement, and mutation of DNA contribute to genome evolution, CONCEPT 21.6 Comparing genome sequences provides clues to evolution and development, 22  Descent with Modification: A Darwinian View of Life, CONCEPT 22.1 The Darwinian revolution challenged traditional views of a young Earth inhabited by unchanging species, CONCEPT 22.2 Descent with modification by natural selection explains the adaptations of organisms and the unity and diversity of life, CONCEPT 22.3 Evolution is supported by an overwhelming amount of scientific evidence, CONCEPT 23.1 Genetic variation makes evolution possible, CONCEPT 23.2 The Hardy-Weinberg equation can be used to test whether a population is evolving, CONCEPT 23.3 Natural selection, genetic drift, and gene flow can alter allele frequencies in a population, CONCEPT 23.4 Natural selection is the only mechanism that consistently causes adaptive evolution, CONCEPT 24.1 The biological species concept emphasizes reproductive isolation, CONCEPT 24.2 Speciation can take place with or without geographic separation, CONCEPT 24.3 Hybrid zones reveal factors that cause reproductive isolation, CONCEPT 24.4 Speciation can occur rapidly or slowly and can result from changes in few or many genes, CONCEPT 25.1 Conditions on early Earth made the origin of life possible, CONCEPT 25.2 The fossil record documents the history of life, CONCEPT 25.3 Key events in life’s history include the origins of unicellular and multicellular organisms and the colonization of land, CONCEPT 25.4 The rise and fall of groups of organisms reflect differences in speciation and extinction rates, CONCEPT 25.5 Major changes in body form can result from changes in the sequences and regulation of developmental genes, CONCEPT 25.6 Evolution is not goal oriented, UNIT 5  THE EVOLUTIONARY HISTORY OF BIOLOGICAL DIVERSITY, CONCEPT 26.1 Phylogenies show evolutionary relationships, CONCEPT 26.2 Phylogenies are inferred from morphological and molecular data, CONCEPT 26.3 Shared characters are used to construct phylogenetic trees, CONCEPT 26.4 An organism’s evolutionary history is documented in its genome, CONCEPT 26.5 Molecular clocks help track evolutionary time, CONCEPT 26.6 Our understanding of the tree of life continues to change based on new data, CONCEPT 27.1 Structural and functional adaptations contribute to prokaryotic success, CONCEPT 27.2 Rapid reproduction, mutation, and genetic recombination promote genetic diversity in prokaryotes, CONCEPT 27.3 Diverse nutritional and metabolic adaptations have evolved in prokaryotes, CONCEPT 27.4 Prokaryotes have radiated into a diverse set of lineages, CONCEPT 27.5 Prokaryotes play crucial roles in the biosphere, CONCEPT 27.6 Prokaryotes have both beneficial and harmful impacts on humans, CONCEPT 28.1 Most eukaryotes are single-celled organisms, CONCEPT 28.2 Excavates include protists with modified mitochondria and protists with unique flagella, CONCEPT 28.3 SAR is a highly diverse group of protists defined by DNA similarities, CONCEPT 28.4 Red algae and green algae are the closest relatives of land plants, CONCEPT 28.5 Unikonts include protists that are closely related to fungi and animals, CONCEPT 28.6 Protists play key roles in ecological communities, 29  Plant Diversity I: How Plants Colonized Land, CONCEPT 29.1 Plants evolved from green algae, CONCEPT 29.2 Mosses and other nonvascular plants have life cycles dominated by gametophytes, CONCEPT 29.3 Ferns and other seedless vascular plants were the first plants to grow tall, 30  Plant Diversity II: The Evolution of Seed Plants, CONCEPT 30.1 Seeds and pollen grains are key adaptations for life on land, CONCEPT 30.2 Gymnosperms bear “naked” seeds, typically on cones, CONCEPT 30.3 The reproductive adaptations of angiosperms include flowers and fruits, CONCEPT 30.4 Human welfare depends on seed plants, CONCEPT 31.1 Fungi are heterotrophs that feed by absorption, CONCEPT 31.2 Fungi produce spores through sexual or asexual life cycles, CONCEPT 31.3 The ancestor of fungi was an aquatic, single-celled, flagellated protist, CONCEPT 31.4 Fungi have radiated into a diverse set of lineages, CONCEPT 31.5 Fungi play key roles in nutrient cycling, ecological interactions, and human welfare, CONCEPT 32.1 Animals are multicellular, heterotrophic eukaryotes with tissues that develop from embryonic layers, CONCEPT 32.2 The history of animals spans more than half a billion years, CONCEPT 32.3 Animals can be characterized by “body plans”, CONCEPT 32.4 Views of animal phylogeny continue to be shaped by new molecular and morphological data, CONCEPT 33.1 Sponges are basal animals that lack tissues, CONCEPT 33.2 Cnidarians are an ancient phylum of eumetazoans, CONCEPT 33.3 Lophotrochozoans, a clade identified by molecular data, have the widest range of animal body forms, CONCEPT 33.4 Ecdysozoans are the most species-rich animal group, CONCEPT 33.5 Echinoderms and chordates are deuterostomes, 34  The Origin and Evolution of Vertebrates, CONCEPT 34.1 Chordates have a notochord and a dorsal, hollow nerve cord, CONCEPT 34.2 Vertebrates are chordates that have a backbone, CONCEPT 34.3 Gnathostomes are vertebrates that have jaws, CONCEPT 34.4 Tetrapods are gnathostomes that have limbs, CONCEPT 34.5 Amniotes are tetrapods that have a terrestrially adapted egg, CONCEPT 34.6 Mammals are amniotes that have hair and produce milk, CONCEPT 34.7 Humans are mammals that have a large brain and bipedal locomotion, 35  Vascular Plant Structure, Growth, and Development, CONCEPT 35.1 Plants have a hierarchical organization consisting of organs, tissues, and cells, CONCEPT 35.2 Different meristems generate new cells for primary and secondary growth, CONCEPT 35.3 Primary growth lengthens roots and shoots, CONCEPT 35.4 Secondary growth increases the diameter of stems and roots in woody plants, CONCEPT 35.5 Growth, morphogenesis, and cell differentiation produce the plant body, 36  Resource Acquisition and Transport in Vascular Plants, CONCEPT 36.1 Adaptations for acquiring resources were key steps in the evolution of vascular plants, CONCEPT 36.2 Different mechanisms transport substances over short or long distances, CONCEPT 36.3 Transpiration drives the transport of water and minerals from roots to shoots via the xylem, CONCEPT 36.4 The rate of transpiration is regulated by stomata, CONCEPT 36.5 Sugars are transported from sources to sinks via the phloem, CONCEPT 36.6 The symplast is highly dynamic, CONCEPT 37.1 Soil contains a living, complex ecosystem, CONCEPT 37.2 Plant roots absorb essential elements from the soil, CONCEPT 37.3 Plant nutrition often involves relationships with other organisms, 38  Angiosperm Reproduction and Biotechnology, CONCEPT 38.1 Flowers, double fertilization, and fruits are key features of the angiosperm life cycle, CONCEPT 38.2 Flowering plants reproduce sexually, asexually, or both, CONCEPT 38.3 People modify crops by breeding and genetic engineering, 39  Plant Responses to Internal and External Signals, CONCEPT 39.1 Signal transduction pathways link signal reception to response, CONCEPT 39.2 Plant hormones help coordinate growth, development, and responses to stimuli, CONCEPT 39.3 Responses to light are critical for plant success, CONCEPT 39.4 Plants respond to a wide variety of stimuli other than light, CONCEPT 39.5 Plants respond to attacks by pathogens and herbivores, 40  Basic Principles of Animal Form and Function, CONCEPT 40.1 Animal form and function are correlated at all levels of organization, CONCEPT 40.2 Feedback control maintains the internal environment in many animals, CONCEPT 40.3 Homeostatic processes for thermoregulation involve form, function, and behavior, CONCEPT 40.4 Energy requirements are related to animal size, activity, and environment, CONCEPT 41.1 An animal’s diet must supply chemical energy, organic building blocks, and essential nutrients, CONCEPT 41.2 Food processing involves ingestion, digestion, absorption, and elimination, CONCEPT 41.3 Organs specialized for sequential stages of food processing form the mammalian digestive system, CONCEPT 41.4 Evolutionary adaptations of vertebrate digestive systems correlate with diet, CONCEPT 41.5 Feedback circuits regulate digestion, energy storage, and appetite, CONCEPT 42.1 Circulatory systems link exchange surfaces with cells throughout the body, CONCEPT 42.2 Coordinated cycles of heart contraction drive double circulation in mammals, CONCEPT 42.3 Patterns of blood pressure and flow reflect the structure and arrangement of blood vessels, CONCEPT 42.4 Blood components function in exchange, transport, and defense, CONCEPT 42.5 Gas exchange occurs across specialized respiratory surfaces, CONCEPT 42.6 Breathing ventilates the lungs, CONCEPT 42.7 Adaptations for gas exchange include pigments that bind and transport gases, CONCEPT 43.1 In innate immunity, recognition and response rely on traits common to groups of pathogens, CONCEPT 43.2 In adaptive immunity, receptors provide pathogen-specific recognition, CONCEPT 43.3 Adaptive immunity defends against infection of body fluids and body cells, CONCEPT 43.4 Disruptions in immune system function can elicit or exacerbate disease, CONCEPT 44.1 Osmoregulation balances the uptake and loss of water and solutes, CONCEPT 44.2 An animal’s nitrogenous wastes reflect its phylogeny and habitat, CONCEPT 44.3 Diverse excretory systems are variations on a tubular theme, CONCEPT 44.4 The nephron is organized for stepwise processing of blood filtrate, CONCEPT 44.5 Hormonal circuits link kidney function, water balance, and blood pressure, CONCEPT 45.1 Hormones and other signaling molecules bind to target receptors, triggering specific response pathways, CONCEPT 45.2 Feedback regulation and coordination with the nervous system are common in hormone pathways, CONCEPT 45.3 Endocrine glands respond to diverse stimuli in regulating homeostasis, development, and behavior, CONCEPT 46.1 Both asexual and sexual reproduction occur in the animal kingdom, CONCEPT 46.2 Fertilization depends on mechanisms that bring together sperm and eggs of the same species, CONCEPT 46.3 Reproductive organs produce and transport gametes, CONCEPT 46.4 The interplay of tropic and sex hormones regulates mammalian reproduction, CONCEPT 46.5 In placental mammals, an embryo develops fully within the mother’s uterus, CONCEPT 47.1 Fertilization and cleavage initiate embryonic development, CONCEPT 47.2 Morphogenesis in animals involves specific changes in cell shape, position, and survival, CONCEPT 47.3 Cytoplasmic determinants and inductive signals regulate cell fate, CONCEPT 48.1 Neuron structure and organization reflect function in information transfer, CONCEPT 48.2 Ion pumps and ion channels establish the resting potential of a neuron, CONCEPT 48.3 Action potentials are the signals conducted by axons, CONCEPT 48.4 Neurons communicate with other cells at synapses, CONCEPT 49.1 Nervous systems consist of circuits of neurons and supporting cells, CONCEPT 49.2 The vertebrate brain is regionally specialized, CONCEPT 49.3 The cerebral cortex controls voluntary movement and cognitive functions, CONCEPT 49.4 Changes in synaptic connections underlie memory and learning, CONCEPT 49.5 Many nervous system disorders can be explained in molecular terms, CONCEPT 50.1 Sensory receptors transduce stimulus energy and transmit signals to the central nervous system, CONCEPT 50.2 In hearing and equilibrium, mechanoreceptors detect moving fluid or settling particles, CONCEPT 50.3 The diverse visual receptors of animals depend on light-absorbing pigments, CONCEPT 50.4 The senses of taste and smell rely on similar sets of sensory receptors, CONCEPT 50.5 The physical interaction of protein filaments is required for muscle function, CONCEPT 50.6 Skeletal systems transform muscle contraction into locomotion, CONCEPT 51.1 Discrete sensory inputs can stimulate both simple and complex behaviors, CONCEPT 51.2 Learning establishes specific links between experience and behavior, CONCEPT 51.3 Selection for individual survival and reproductive success can explain diverse behaviors, CONCEPT 51.4 Genetic analyses and the concept of inclusive fitness provide a basis for studying the evolution of behavior, 52  An Introduction to Ecology and the Biosphere, CONCEPT 52.1 Earth’s climate varies by latitude and season and is changing rapidly, CONCEPT 52.2 The distribution of terrestrial biomes is controlled by climate and disturbance, CONCEPT 52.3 Aquatic biomes are diverse and dynamic systems that cover most of Earth, CONCEPT 52.4 Interactions between organisms and the environment limit the distribution of species, CONCEPT 52.5Ecological change and evolution affect one another over long and short periods of time, CONCEPT 53.1 Biotic and abiotic factors affectpopulation density, dispersion, and demographics, CONCEPT 53.2 The exponential model describes population growth in an idealized, unlimited environment, CONCEPT 53.3 The logistic model describes how a population grows more slowly as it nears its carrying capacity, CONCEPT 53.4 Life history traits are products of natural selection, CONCEPT 53.5 Density-dependent factors regulate population growth, CONCEPT 53.6 The human population is no longer growing exponentially but is still increasing rapidly, CONCEPT 54.1 Community interactions are classified by whether they help, harm, or have no effect on the species involved, CONCEPT 54.2 Diversity and trophic structure characterize biological communities, CONCEPT 54.3 Disturbance influences species diversity and composition, CONCEPT 54.4 Biogeographic factors affect community diversity, CONCEPT 54.5 Pathogens alter community structure locally and globally, CONCEPT 55.1 Physical laws govern energy flow and chemical cycling in ecosystems, CONCEPT 55.2 Energy and other limiting factors control primary production in ecosystems, CONCEPT 55.3 Energy transfer between trophic levels is typically only 10% efficient, CONCEPT 55.4 Biological and geochemical processes cycle nutrients and water in ecosystems, CONCEPT 55.5 Restoration ecologists return degraded ecosystems to a more natural state, 56  Conservation Biology and Global Change, CONCEPT 56.1 Human activities threaten Earth’s biodiversity, CONCEPT 56.2 Population conservation focuses on population size, genetic diversity, and critical habitat, CONCEPT 56.3 Landscape and regional conservation help sustain biodiversity, CONCEPT 56.4 Earth is changing rapidly as a result of human actions, CONCEPT 56.5 Sustainable development can improve human lives while conserving biodiversity.